利用5-芳基偶氮-2,3,6-三取代吡啶的[4 + 1]环加成反应合成2-芳基-3-二甲基氨基吡唑并-[3,4- c ]吡啶的策略
摘要:
为了探讨最近发现的基于[4 + 1]环加成反应的吡唑并[3,4- c ]吡啶衍生物的制备方法的可行性和一般性,该策略是一系列5-芳基偶氮-2,3,6-的成员通过3-氧代-2-芳基肼基丙醛与3-氧代-3-苯基丙腈的反应制备三取代的吡啶。结果表明3-氧代-3-苯基丙腈与底物反应,该底物在芳基hydr部分的N-芳基环上不包含吸电子取代基,从而有效地产生6-芳基-2-苯基-5-芳基氮杂腈。相反,在3-氧代-2-芳基肼基丙醛的反应中生成2-氨基-6-芳基-5-芳基偶氮-3-苯甲酰基吡啶,其在N上含有吸电子取代基。-芳基部分。以预测的方式,6-芳基-2-苯基-5-芳基氮杂腈与二甲基甲酰胺二甲基乙缩醛(DMF-DMA)进行平滑反应,从而导致形成一类新的2-芳基-3-二甲基氨基吡唑并[3,4- c ]吡啶。此过程的机理涉及[4 + 1]环加成反应,该反应通过将由DMF-DMA生成的二甲氨基)甲氧基卡宾的初
Synthesis of A New Class of Pyridazin-3-one and 2-Amino-5-arylazopyridine Derivatives and Their Utility in the Synthesis of Fused Azines
作者:Hamada Ibrahim、Haider Behbehani
DOI:10.3390/molecules19022637
日期:——
A general route for the synthesis of a novel class of pyridazin-3-one derivatives 3 by the reaction in acetic anhydride between 3-oxo-2-arylhydrazonopropanals 1 and some active methylene compounds like p-nitrophenylacetic acid and cyanoacetic acid was established. Under these conditions the pyridazin-3-one derivatives 3 were formed as the sole isolable products in excellent yield. The 6-acetyl-3-oxopyridazine derivative 3l was reacted with DMF-DMA to afford the corresponding enaminone derivative 4, which reacts with a variety of aminoazoles to afford the corresponding azolo[1,5-a]pyrimidine derivatives 5–7. Also, in order to explore the viability and generality of a recently uncovered reaction between 3-oxo-2-arylhydrazonopropanals and active methylene compounds, a variety of 2-amino-6-aryl-5-arylazo-3-aroylpyridines 16–19 were prepared by reacting 3-oxo-2-arylhydrazonopropanals with miscellaneous active methylene compounds like 3-oxo-3-phenylpropionitrile, hetaroylacetonitriles and cyanoacetamides. These 2-aminopyridine derivatives undergo smooth reactions with cyanoacetic acid that led to the formation in high yield of a new class of 1,8-naphthyridine derivatives 24. The structures of all new substances prepared in this investigation were determined by the different analytical spectroscopic methods, in addition to the X-ray crystallographic analysis.
A strategy for the synthesis of 2-aryl-3-dimethylaminopyrazolo-[3,4-c]pyridines that utilizes [4+1] cycloaddition reactions of 5-arylazo-2,3,6-trisubstituted pyridines
作者:Haider Behbehani、Hamada Mohamed Ibrahim
DOI:10.1016/j.tet.2013.10.061
日期:2013.12
In order to explore the viability and generality of a recently uncovered [4+1] cycloaddition based strategy for the preparation of pyrazolo[3,4-c]pyridine derivatives, members of a series of 5-arylazo-2,3,6-trisubstituted pyridines were prepared by reactions of 3-oxo-2-arylhydrazonopropanals with 3-oxo-3-phenylpropionitrile. The results show that 3-oxo-3-phenylpropionitrile reacts with hydrazone substrates
为了探讨最近发现的基于[4 + 1]环加成反应的吡唑并[3,4- c ]吡啶衍生物的制备方法的可行性和一般性,该策略是一系列5-芳基偶氮-2,3,6-的成员通过3-氧代-2-芳基肼基丙醛与3-氧代-3-苯基丙腈的反应制备三取代的吡啶。结果表明3-氧代-3-苯基丙腈与底物反应,该底物在芳基hydr部分的N-芳基环上不包含吸电子取代基,从而有效地产生6-芳基-2-苯基-5-芳基氮杂腈。相反,在3-氧代-2-芳基肼基丙醛的反应中生成2-氨基-6-芳基-5-芳基偶氮-3-苯甲酰基吡啶,其在N上含有吸电子取代基。-芳基部分。以预测的方式,6-芳基-2-苯基-5-芳基氮杂腈与二甲基甲酰胺二甲基乙缩醛(DMF-DMA)进行平滑反应,从而导致形成一类新的2-芳基-3-二甲基氨基吡唑并[3,4- c ]吡啶。此过程的机理涉及[4 + 1]环加成反应,该反应通过将由DMF-DMA生成的二甲氨基)甲氧基卡宾的初